Electric stoves

ABSTRACT

Electric stoves in which the relative vertical movement of a pot support and an electric heating element is controlled to control heat, the heating element and the pot support having surface means in horizontal planes. The surface means of the heating element may include at least one portion interposed between horizontally spaced portions of the surface means of the pot support, the heating element preferably including a plurality of generally annular portions at differing radial distances from a central vertical axis. In another embodiment, the pot support includes a thin flat plate portion. In one type of construction, the heating element is moved vertically while in another the pot support is moved vertically. Important features of the invention relate to means for controlling the relative vertical movement, both manually and automatically, with temperature sensing means being usable in conjunction with the control. The control means may control electrical energization of the heating element while also controlling the relative movement of the heating element and the pot support.

United States Patent [72] Inventor Benedictlngrao ElmwoodParkJll. [21] AppLNo. 693,270 [22] Filed Dec.26,1967 [45] Patented May 18,1971 [73} Assignee JohnlngroJr.

Albuquerque, N. Mex. lractionalpartinterest [54] ELECTRIC STOVES 50Claims,48DrawingFigs. [52] U.S.Cl 219/444, 219/403, 219/455, 219/465, 99/337 [51] lnt.Cl 1105113/68 [50] FieldofSearch ..219/455-6, 444, 403; 219/465, 37.4, 535; 99/337 [56] References Cited UNITED STATES PATENTS 1,704,413 3/1929 Wait 219/535 2,250,357 7/1941 Cha1let.... 219/456 2,272,658 2/1942 Challet.... 2l9/456X 2,810,058 10/1957 Fernico... 219/465 2,874,261 2/1959 Wolf 219/456 3,384,735 5/1968 Linger 219/456 7A 6A 7B 68 7c 13 47 7 Z 1 9 I l t 392 13B /8 ll 7D 11 19 I 17A 18C I 390 1.

1,102,392 7/1914 Denhard 3,440,406 4/1969 Sego,Jr.

Primary Examinervolodymyr Y. Mayewsky Attorney-Alberts, Brezina and Lund ABSTRACT: Electric stoves in which the relative vertical movement of a pot support and an electric heating element is controlled to control heat, the heating element and the pot support having surface means in horizontal planes. The surface means of the heating element may include at least one portion interposed between horizontally spaced portions of the surface means of the pot support, the heating element preferably including a plurality of generally annular portions at differing-radial distances from a central vertical axis. In another embodiment, the pot support includes a thin flat plate portion. In one type of construction, the heating element is moved vertically while in another the pot support is moved vertically. Important features of the invention relate to means for controlling the relative vertical movement, both manually and automatically, with temperature sensing means being usable in conjunction with the control. The control means may control electrical energization of the heating element while also controlling the relative movement of the heating element and the pot support.

7B 6 A 3 7A 2 188 [I1 i13C n 1 ,3 174 10A 8A 173 10 1735 11A 9A 66 37 173A 1B "1 1 5 14 189 13A u,

Patented May 18, 1911 3,578,951

22 Sheets-Sheet 1 FIG. I

J g j INVENTOR BENEDICT I NG RAO M W-IM Patented May 18, 1971 22 Sheets-Sheet 2 RON INVENTOR BENEDICT INGRAO BY ,Patent ed May 18, 197 1 22. Sheets- Sheet 5 ow 3 5w I NVENTOR BENEDICT I NGRAO MAUI 390' n n l\\ 22 Sheets-Sheet 4 INVENTOR BENEDICT INGRAO m, Wfm

-; Patented May 18, 1971 22 Sheets-Sheet 6 INVENTOR BENEDICT I NGRAO I Patgnted -May 18, 1911 3,578,951

22 ShoetE-Shcet 7 INVENT R BENEDICT INGRAO Patent ed} "May 18, 1971 22 She ts-Sheet a 198A 198 197C 197 196 202 201 198B 200 199 197A INVENTOR BENEDICT INGRAO Pate'fited May 18, 1911 22 Sheets-Sheet 16 wow a wmm H m 4 INVENTOR BENEDICT INGRAO W WM Patented May 18, 1971 22 Sheets-Sheet 19 INVENTOR BENEDICT INGRAO 

1. In an electric stove, a pot support having surface means in a horizontal plane engageable with the underside surface of a pot, an electric heating element having surface means in a horizontal plane positionable in proximity to said underside surface of the pot, first support means for said pot support, second support means for said heating element, control means for effecting relative vertical movement of said first and second support means between first and second limits of relative movement, said surface means of said heating element being positioned above said surface means of said pot support at said first limit of relative movement and with no pot on said heating element and being positioned a substantial distance below said surface means of said pot support at said second limit of relative movement, and yieldable means associated with said second support means and operative at said first limit of relative movement to allow the weight of a pot to lower said heating element to a position such that The underside of the pot engages both said surface means of said heating element and said surface means of said pot support.
 2. In an electric stove as defined in claim 1, said surface means of said pot support including a plurality of horizontally spaced portions, and said surface means of said heating element including at least one portion interposed between said horizontally spaced portions of said surface means of said pot support.
 3. In an electric stove as defined in claim 2, said surface means of said heating element including a plurality of generally annular portions at differing radial distances from a central vertical axis and interposed between said horizontally spaced portions of said surface means of said pot support.
 4. In an electric stove as defined in claim 1, a horizontal wall having an opening therein, and means for supporting said pot support generally within said opening.
 5. In an electric stove as defined in claim 4, an upstanding ridge around said opening to prevent flow of liquids into said opening.
 6. In an electric stove as defined in claim 5, said pot support including an outer ring portion above said ridge.
 7. In an electric stove as defined in claim 1, said pot support including a thin flat horizontal plate portion having an upper surface defining said surface means thereof, and said surface means of said heating element being engageable with the lower surface of said thin flat horizontal plate portion.
 8. In an electric stove as defined in claim 7, said thin flat horizontal plate portion being perforated.
 9. In an electric stove as defined in claim 7, a horizontal wall having an opening therein, and means supporting said pot support in said opening including a plurality of depending spring fingers at peripherally spaced points of said horizontal plate portion engageable with the edge of said top wall opening.
 10. In an electric stove as defined in claim 7, a horizontal wall having an opening therein, and means supporting said pot support in said opening with said upper surface thereof in a plane in spaced relation above the plane of the upper surface of said wall, said pot support including a peripheral edge portion beveled downwardly to said wall outside said opening.
 11. In an electric stove as defined in claim 1, said control means including a manually actuatable element.
 12. In an electric stove as defined in claim 1, said control means including an electrically driven drive element.
 13. In an electric stove as defined in claim 1, said control means including temperature responsive means for controlling the relative position of said heating element and said pot support in accordance with the temperature of the underside of the pot.
 14. In an electric stove as defined in claim 13, said temperature responsive means including electrical temperature sensing means, and electromechanical means controlled by said sensing means for controlling the relative position of said heating element and said pot support.
 15. In an electric stove as defined in claim 13, said temperature responsive means including a thermal element deformed in accordance with the temperature of the underside of the pot, and means mechanically coupled to said element for controlling the relative position of said heating element and said pot support.
 16. In an electric stove as defined in claim 1, manually actuatable temperature setting means, means controlled by said temperature setting means for controlling the electrical energization of said heating element, and means controlled by said temperature setting means for controlling said control means for effecting relative vertical movement of said pot support and said heating element.
 17. In an electric stove as defined in claim 1, said pot support being stationary, and said control means being operative to move said heating element downwardly away from the pot, and means for holding said heating element in a downward position.
 18. In an electric stove as defineD in claim 17, means including time delay means for automatically releasing said holding means and raising said heating element after a certain time delay period.
 19. In an electric stove as defined in claim 18, said time delay means including a thermostatic element.
 20. In an electric stove as defined in claim 18, said time delay means including geared mechanical escapement means.
 21. In an electric stove as defined in claim 1, said second support means including a vertically movable support centrally located with respect to said heating element, and a connection between said heating element and said vertically movable support arranged to allow tilting movement of said heating element.
 22. In an electric stove as defined in claim 21, stabilizing means for limiting said tilting movement of said heating element.
 23. In an electric stove as defined in claim 1, said second support means including a vertically extending elongated support, means journaling said support for vertical movement along a vertical axis centrally located with respect to said heating element, means restraining said support against rotation about said axis, and means connecting said heating element to an upper end portion of said support, said connecting means being operative to restrain said heating element against rotation relative to said support.
 24. In an electric stove as defined in claim 1, said control means including a lever.
 25. In an electric stove as defined in claim 1, said control means including a solenoid.
 26. In an electric stove as defined in claim 1, said control means including an electric motor.
 27. In an electric stove as defined in claim 1, said control means including a manually rotatable control element, and cam means actuated by rotation of said control element.
 28. In an electric stove as defined in claim 1, a stationary frame structure, said first support means and said pot support being carried by said frame structure, said yieldable means being operative between said second support means and said frame structure to urge said heating element upwardly toward the pot, and said control means being operative against the action of said yieldable means to lower said second support means and said heating element.
 29. In an electric stove as defined in claim 28, means for releasably latching said heating element in a downward position.
 30. In an electric stove as defined in claim 29, means restraining said heating element against rapid upward movement upon release of said latching means.
 31. In an electric stove as defined in claim 1, said pot support including a thin flat horizontal plate portion having an upper surface defining said surface means thereof, and said control means including spring means for urging said heating element upwardly relative to said pot support to normally press said heating element into engagement with the under surface of said plate portion.
 32. In an electric stove as defined in claim 1, tilting action means for supporting said heating element to normally obtain maximum area of contact with the pot.
 33. In an electric stove as defined in claim 1, said heating element being substantially stationary, and said control means being operative to move said pot support upwardly to lift the pot off said heating element.
 34. In an electric stove as defined in claim 33, latch means for latching said pot support in an upward position.
 35. In an electric stove as defined in claim 34, means for releasing said latch means after elapse of a time interval.
 36. In an electric stove as defined in claim 33, manually actuatable means for releasing said latch means.
 37. In an electric stove as defined in claim 33, a vertically movable support structure operated by said control means and arranged to support said pot support while limiting tilting movement of said pot support.
 38. In an electric stove as defined in claim 37, said pot support being liftable off said support structure.
 39. In an electric stovE as defined in claim 1, said control means including a manually depressible pushbutton element.
 40. In an electric stove as defined in claim 39, said control means being operative to effect relative vertical movement of said pot support and said heating element in a direction such that the underside of the pot is separated from said heating element when said pushbutton element is depressed.
 41. In an electric stove as defined in claim 1, said control means including manually actuatable means, means controlled by said manually actuatable means to control electrical energization of said heating element, said manually actuatable means having an off position in which said heating element is deenergized and in which the underside of the pot is vertically separated from said heating element.
 42. In an electric stove as defined in claim 1, means associated with said control means for indicating the relative vertical position of said pot support and said heating element.
 43. In an electric stove as defined in claim 1, said control means including a pair of shafts journaled in spaced parallel horizontal axes, a pair of intermeshed gears on said shafts having the same pitch diameter, and a pair of arms on said shafts for effecting said relative vertical movement of said pot support and said heating element.
 44. In an electric stove as defined in claim 43, said heating element being stationary and said arms being arranged to lift said support.
 45. In an electric stove as defined in claim 1, said control means including a manually actuatable element, means controllable by said manually actuatable element for adjusting the relative vertical position of said heating element and said pot support, means controllable by said manually actuatable element for latching said heating element and said pot support in relative vertical relationship, and means for automatically releasing said latching means.
 46. In an electric stove as defined in claim 17, means for manually releasing said holding means.
 47. In an electric stove as defined in claim 1, said pot support including air channel means to permit escapement of trapped hot air with a pot thereon.
 48. In an electric stove as defined in claim 1, said surface means of said heating element including a plurality of horizontally spaced portions, and said surface means of said pot support including at least one portion interposed between said horizontally spaced portions of said surface means of said heating element.
 49. In an electric stove as defined in claim 48, said one portion of said surface means of said pot support being a radially extending portion.
 50. In an electric stove as defined in claim 1, means including a hinged connection for supporting said heating element. 